I found the option 'Requires a minimum number of successful builds'. Stops pull requests from being merged if they have any unsuccessful builds. Even if I set number to 1 Bitbucket check ALL builds. I have sometimes the pull request succeed, 2 other builds succeed and 1 build failed. And do not want to block pull request at this time.

If I set this number to 0, Bitbucket do not check the pull request build status